<?php

// +----------------------------------------------------------------------

// | TOPThink [ WE CAN DO IT JUST THINK ]

// +----------------------------------------------------------------------

// | Copyright (c) 2010 http://topthink.com All rights reserved.

// +----------------------------------------------------------------------

// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )

// +----------------------------------------------------------------------

// | Author: 麦当苗儿 <zuojiazi@vip.qq.com> <http://www.zjzit.cn>

// +----------------------------------------------------------------------

// | GIF.class.php 2013-03-09

// +----------------------------------------------------------------------

namespace Think\Image\Driver;

class GIF{

	/**

	 * GIF帧列表

	 * @var array

	 */

	private $frames = array();



	/**

	 * 每帧等待时间列表

	 * @var array

	 */

	private $delays = array();



	/**

	 * 构造方法，用于解码GIF图片

	 * @param string $src GIF图片数据

	 * @param string $mod 图片数据类型

	 */

	public function __construct($src = null, $mod = 'url') {

		if(!is_null($src)){

			if('url' == $mod && is_file($src)){

				$src = file_get_contents($src);

			}

			

			/* 解码GIF图片 */

			try{

				$de = new GIFDecoder($src);

				$this->frames = $de->GIFGetFrames();

				$this->delays = $de->GIFGetDelays();

			} catch(Exception $e){

				E("解码GIF图片出错");

			}

		}

	}



	/**

	 * 设置或获取当前帧的数据

	 * @param  string $stream 二进制数据流

	 * @return boolean        获取到的数据

	 */

	public function image($stream = null){

		if(is_null($stream)){

			$current = current($this->frames);

			return false === $current ? reset($this->frames) : $current;

		} else {

			$this->frames[key($this->frames)] = $stream;

		}

	}



	/**

	 * 将当前帧移动到下一帧

	 * @return string 当前帧数据

	 */

	public function nextImage(){

		return next($this->frames);

	}



	/**

	 * 编码并保存当前GIF图片

	 * @param  string $gifname 图片名称

	 */

	public function save($gifname){

		$gif = new GIFEncoder($this->frames, $this->delays, 0, 2, 0, 0, 0, 'bin');

		file_put_contents($gifname, $gif->GetAnimation());

	}



}





/*

:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::

::

::	GIFEncoder Version 2.0 by László Zsidi, http://gifs.hu

::

::	This class is a rewritten 'GifMerge.class.php' version.

::

::  Modification:

::   - Simplified and easy code,

::   - Ultra fast encoding,

::   - Built-in errors,

::   - Stable working

::

::

::	Updated at 2007. 02. 13. '00.05.AM'

::

::

::

::  Try on-line GIFBuilder Form demo based on GIFEncoder.

::

::  http://gifs.hu/phpclasses/demos/GifBuilder/

::

:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::

*/



Class GIFEncoder {

	var $GIF = "GIF89a";		/* GIF header 6 bytes	*/

	var $VER = "GIFEncoder V2.05";	/* Encoder version		*/



	var $BUF = Array ( );

	var $LOP =  0;

	var $DIS =  2;

	var $COL = -1;

	var $IMG = -1;



	var $ERR = Array (

		'ERR00'=>"Does not supported function for only one image!",

		'ERR01'=>"Source is not a GIF image!",

		'ERR02'=>"Unintelligible flag ",

		'ERR03'=>"Does not make animation from animated GIF source",

	);



	/*

	:::::::::::::::::::::::::::::::::::::::::::::::::::

	::

	::	GIFEncoder...

	::

	*/

	function GIFEncoder	(

							$GIF_src, $GIF_dly, $GIF_lop, $GIF_dis,

							$GIF_red, $GIF_grn, $GIF_blu, $GIF_mod

						) {

		if ( ! is_array ( $GIF_src ) && ! is_array ( $GIF_tim ) ) {

			printf	( "%s: %s", $this->VER, $this->ERR [ 'ERR00' ] );

			exit	( 0 );

		}

		$this->LOP = ( $GIF_lop > -1 ) ? $GIF_lop : 0;

		$this->DIS = ( $GIF_dis > -1 ) ? ( ( $GIF_dis < 3 ) ? $GIF_dis : 3 ) : 2;

		$this->COL = ( $GIF_red > -1 && $GIF_grn > -1 && $GIF_blu > -1 ) ?

						( $GIF_red | ( $GIF_grn << 8 ) | ( $GIF_blu << 16 ) ) : -1;



		for ( $i = 0; $i < count ( $GIF_src ); $i++ ) {

			if ( strToLower ( $GIF_mod ) == "url" ) {

				$this->BUF [ ] = fread ( fopen ( $GIF_src [ $i ], "rb" ), filesize ( $GIF_src [ $i ] ) );

			}

			else if ( strToLower ( $GIF_mod ) == "bin" ) {

				$this->BUF [ ] = $GIF_src [ $i ];

			}

			else {

				printf	( "%s: %s ( %s )!", $this->VER, $this->ERR [ 'ERR02' ], $GIF_mod );

				exit	( 0 );

			}

			if ( substr ( $this->BUF [ $i ], 0, 6 ) != "GIF87a" && substr ( $this->BUF [ $i ], 0, 6 ) != "GIF89a" ) {

				printf	( "%s: %d %s", $this->VER, $i, $this->ERR [ 'ERR01' ] );

				exit	( 0 );

			}

			for ( $j = ( 13 + 3 * ( 2 << ( ord ( $this->BUF [ $i ] { 10 } ) & 0x07 ) ) ), $k = TRUE; $k; $j++ ) {

				switch ( $this->BUF [ $i ] { $j } ) {

					case "!":

						if ( ( substr ( $this->BUF [ $i ], ( $j + 3 ), 8 ) ) == "NETSCAPE" ) {

							printf	( "%s: %s ( %s source )!", $this->VER, $this->ERR [ 'ERR03' ], ( $i + 1 ) );

							exit	( 0 );

						}

						break;

					case ";":

						$k = FALSE;

						break;

				}

			}

		}

		GIFEncoder::GIFAddHeader ( );

		for ( $i = 0; $i < count ( $this->BUF ); $i++ ) {

			GIFEncoder::GIFAddFrames ( $i, $GIF_dly [ $i ] );

		}

		GIFEncoder::GIFAddFooter ( );

	}

	/*

	:::::::::::::::::::::::::::::::::::::::::::::::::::

	::

	::	GIFAddHeader...

	::

	*/

	function GIFAddHeader ( ) {

		$cmap = 0;



		if ( ord ( $this->BUF [ 0 ] { 10 } ) & 0x80 ) {

			$cmap = 3 * ( 2 << ( ord ( $this->BUF [ 0 ] { 10 } ) & 0x07 ) );



			$this->GIF .= substr ( $this->BUF [ 0 ], 6, 7		);

			$this->GIF .= substr ( $this->BUF [ 0 ], 13, $cmap	);

			$this->GIF .= "!\377\13NETSCAPE2.0\3\1" . GIFEncoder::GIFWord ( $this->LOP ) . "\0";

		}

	}

	/*

	:::::::::::::::::::::::::::::::::::::::::::::::::::

	::

	::	GIFAddFrames...

	::

	*/

	function GIFAddFrames ( $i, $d ) {



		$Locals_str = 13 + 3 * ( 2 << ( ord ( $this->BUF [ $i ] { 10 } ) & 0x07 ) );



		$Locals_end = strlen ( $this->BUF [ $i ] ) - $Locals_str - 1;

		$Locals_tmp = substr ( $this->BUF [ $i ], $Locals_str, $Locals_end );



		$Global_len = 2 << ( ord ( $this->BUF [ 0  ] { 10 } ) & 0x07 );

		$Locals_len = 2 << ( ord ( $this->BUF [ $i ] { 10 } ) & 0x07 );



		$Global_rgb = substr ( $this->BUF [ 0  ], 13,

							3 * ( 2 << ( ord ( $this->BUF [ 0  ] { 10 } ) & 0x07 ) ) );

		$Locals_rgb = substr ( $this->BUF [ $i ], 13,

							3 * ( 2 << ( ord ( $this->BUF [ $i ] { 10 } ) & 0x07 ) ) );



		$Locals_ext = "!\xF9\x04" . chr ( ( $this->DIS << 2 ) + 0 ) .

						chr ( ( $d >> 0 ) & 0xFF ) . chr ( ( $d >> 8 ) & 0xFF ) . "\x0\x0";



		if ( $this->COL > -1 && ord ( $this->BUF [ $i ] { 10 } ) & 0x80 ) {

			for ( $j = 0; $j < ( 2 << ( ord ( $this->BUF [ $i ] { 10 } ) & 0x07 ) ); $j++ ) {

				if	(

						ord ( $Locals_rgb { 3 * $j + 0 } ) == ( ( $this->COL >> 16 ) & 0xFF ) &&

						ord ( $Locals_rgb { 3 * $j + 1 } ) == ( ( $this->COL >>  8 ) & 0xFF ) &&

						ord ( $Locals_rgb { 3 * $j + 2 } ) == ( ( $this->COL >>  0 ) & 0xFF )

					) {

					$Locals_ext = "!\xF9\x04" . chr ( ( $this->DIS << 2 ) + 1 ) .

									chr ( ( $d >> 0 ) & 0xFF ) . chr ( ( $d >> 8 ) & 0xFF ) . chr ( $j ) . "\x0";

					break;

				}

			}

		}

		switch ( $Locals_tmp { 0 } ) {

			case "!":

				$Locals_img = substr ( $Locals_tmp, 8, 10 );

				$Locals_tmp = substr ( $Locals_tmp, 18, strlen ( $Locals_tmp ) - 18 );

				break;

			case ",":

				$Locals_img = substr ( $Locals_tmp, 0, 10 );

				$Locals_tmp = substr ( $Locals_tmp, 10, strlen ( $Locals_tmp ) - 10 );

				break;

		}

		if ( ord ( $this->BUF [ $i ] { 10 } ) & 0x80 && $this->IMG > -1 ) {

			if ( $Global_len == $Locals_len ) {

				if ( GIFEncoder::GIFBlockCompare ( $Global_rgb, $Locals_rgb, $Global_len ) ) {

					$this->GIF .= ( $Locals_ext . $Locals_img . $Locals_tmp );

				}

				else {

					$byte  = ord ( $Locals_img { 9 } );

					$byte |= 0x80;

					$byte &= 0xF8;

					$byte |= ( ord ( $this->BUF [ 0 ] { 10 } ) & 0x07 );

					$Locals_img { 9 } = chr ( $byte );

					$this->GIF .= ( $Locals_ext . $Locals_img . $Locals_rgb . $Locals_tmp );

				}

			}

			else {

				$byte  = ord ( $Locals_img { 9 } );

				$byte |= 0x80;

				$byte &= 0xF8;

				$byte |= ( ord ( $this->BUF [ $i ] { 10 } ) & 0x07 );

				$Locals_img { 9 } = chr ( $byte );

				$this->GIF .= ( $Locals_ext . $Locals_img . $Locals_rgb . $Locals_tmp );

			}

		}

		else {

			$this->GIF .= ( $Locals_ext . $Locals_img . $Locals_tmp );

		}

		$this->IMG  = 1;

	}

	/*

	:::::::::::::::::::::::::::::::::::::::::::::::::::

	::

	::	GIFAddFooter...

	::

	*/

	function GIFAddFooter ( ) {

		$this->GIF .= ";";

	}

	/*

	:::::::::::::::::::::::::::::::::::::::::::::::::::

	::

	::	GIFBlockCompare...

	::

	*/

	function GIFBlockCompare ( $GlobalBlock, $LocalBlock, $Len ) {



		for ( $i = 0; $i < $Len; $i++ ) {

			if	(

					$GlobalBlock { 3 * $i + 0 } != $LocalBlock { 3 * $i + 0 } ||

					$GlobalBlock { 3 * $i + 1 } != $LocalBlock { 3 * $i + 1 } ||

					$GlobalBlock { 3 * $i + 2 } != $LocalBlock { 3 * $i + 2 }

				) {

					return ( 0 );

			}

		}



		return ( 1 );

	}

	/*

	:::::::::::::::::::::::::::::::::::::::::::::::::::

	::

	::	GIFWord...

	::

	*/

	function GIFWord ( $int ) {



		return ( chr ( $int & 0xFF ) . chr ( ( $int >> 8 ) & 0xFF ) );

	}

	/*

	:::::::::::::::::::::::::::::::::::::::::::::::::::

	::

	::	GetAnimation...

	::

	*/

	function GetAnimation ( ) {

		return ( $this->GIF );

	}

}





/*

:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::

::

::	GIFDecoder Version 2.0 by László Zsidi, http://gifs.hu

::

::	Created at 2007. 02. 01. '07.47.AM'

::

::

::

::

::  Try on-line GIFBuilder Form demo based on GIFDecoder.

::

::  http://gifs.hu/phpclasses/demos/GifBuilder/

::

:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::

*/



Class GIFDecoder {

	var $GIF_buffer = Array ( );

	var $GIF_arrays = Array ( );

	var $GIF_delays = Array ( );

	var $GIF_stream = "";

	var $GIF_string = "";

	var $GIF_bfseek =  0;



	var $GIF_screen = Array ( );

	var $GIF_global = Array ( );

	var $GIF_sorted;

	var $GIF_colorS;

	var $GIF_colorC;

	var $GIF_colorF;



	/*

	:::::::::::::::::::::::::::::::::::::::::::::::::::

	::

	::	GIFDecoder ( $GIF_pointer )

	::

	*/

	function GIFDecoder ( $GIF_pointer ) {

		$this->GIF_stream = $GIF_pointer;



		GIFDecoder::GIFGetByte ( 6 );	// GIF89a

		GIFDecoder::GIFGetByte ( 7 );	// Logical Screen Descriptor



		$this->GIF_screen = $this->GIF_buffer;

		$this->GIF_colorF = $this->GIF_buffer [ 4 ] & 0x80 ? 1 : 0;

		$this->GIF_sorted = $this->GIF_buffer [ 4 ] & 0x08 ? 1 : 0;

		$this->GIF_colorC = $this->GIF_buffer [ 4 ] & 0x07;

		$this->GIF_colorS = 2 << $this->GIF_colorC;



		if ( $this->GIF_colorF == 1 ) {

			GIFDecoder::GIFGetByte ( 3 * $this->GIF_colorS );

			$this->GIF_global = $this->GIF_buffer;

		}

		/*

		 *

		 *  05.06.2007.

		 *  Made a little modification

		 *

		 *

		 -	for ( $cycle = 1; $cycle; ) {

		 +		if ( GIFDecoder::GIFGetByte ( 1 ) ) {

		 -			switch ( $this->GIF_buffer [ 0 ] ) {

		 -				case 0x21:

		 -					GIFDecoder::GIFReadExtensions ( );

		 -					break;

		 -				case 0x2C:

		 -					GIFDecoder::GIFReadDescriptor ( );

		 -					break;

		 -				case 0x3B:

		 -					$cycle = 0;

		 -					break;

		 -		  	}

		 -		}

		 +		else {

		 +			$cycle = 0;

		 +		}

		 -	}

		*/

		for ( $cycle = 1; $cycle; ) {

			if ( GIFDecoder::GIFGetByte ( 1 ) ) {

				switch ( $this->GIF_buffer [ 0 ] ) {

					case 0x21:

						GIFDecoder::GIFReadExtensions ( );

						break;

					case 0x2C:

						GIFDecoder::GIFReadDescriptor ( );

						break;

					case 0x3B:

						$cycle = 0;

						break;

				}

			}

			else {

				$cycle = 0;

			}

		}

	}

	/*

	:::::::::::::::::::::::::::::::::::::::::::::::::::

	::

	::	GIFReadExtension ( )

	::

	*/

	function GIFReadExtensions ( ) {

		GIFDecoder::GIFGetByte ( 1 );

		for ( ; ; ) {

			GIFDecoder::GIFGetByte ( 1 );

			if ( ( $u = $this->GIF_buffer [ 0 ] ) == 0x00 ) {

				break;

			}

			GIFDecoder::GIFGetByte ( $u );

			/*

			 * 07.05.2007.

			 * Implemented a new line for a new function

			 * to determine the originaly delays between

			 * frames.

			 *

			 */

			if ( $u == 4 ) {

				$this->GIF_delays [ ] = ( $this->GIF_buffer [ 1 ] | $this->GIF_buffer [ 2 ] << 8 );

			}

		}

	}

	/*

	:::::::::::::::::::::::::::::::::::::::::::::::::::

	::

	::	GIFReadExtension ( )

	::

	*/

	function GIFReadDescriptor ( ) {

		$GIF_screen	= Array ( );



		GIFDecoder::GIFGetByte ( 9 );

		$GIF_screen = $this->GIF_buffer;

		$GIF_colorF = $this->GIF_buffer [ 8 ] & 0x80 ? 1 : 0;

		if ( $GIF_colorF ) {

			$GIF_code = $this->GIF_buffer [ 8 ] & 0x07;

			$GIF_sort = $this->GIF_buffer [ 8 ] & 0x20 ? 1 : 0;

		}

		else {

			$GIF_code = $this->GIF_colorC;

			$GIF_sort = $this->GIF_sorted;

		}

		$GIF_size = 2 << $GIF_code;

		$this->GIF_screen [ 4 ] &= 0x70;

		$this->GIF_screen [ 4 ] |= 0x80;

		$this->GIF_screen [ 4 ] |= $GIF_code;

		if ( $GIF_sort ) {

			$this->GIF_screen [ 4 ] |= 0x08;

		}

		$this->GIF_string = "GIF87a";

		GIFDecoder::GIFPutByte ( $this->GIF_screen );

		if ( $GIF_colorF == 1 ) {

			GIFDecoder::GIFGetByte ( 3 * $GIF_size );

			GIFDecoder::GIFPutByte ( $this->GIF_buffer );

		}

		else {

			GIFDecoder::GIFPutByte ( $this->GIF_global );

		}

		$this->GIF_string .= chr ( 0x2C );

		$GIF_screen [ 8 ] &= 0x40;

		GIFDecoder::GIFPutByte ( $GIF_screen );

		GIFDecoder::GIFGetByte ( 1 );

		GIFDecoder::GIFPutByte ( $this->GIF_buffer );

		for ( ; ; ) {

			GIFDecoder::GIFGetByte ( 1 );

			GIFDecoder::GIFPutByte ( $this->GIF_buffer );

			if ( ( $u = $this->GIF_buffer [ 0 ] ) == 0x00 ) {

				break;

			}

			GIFDecoder::GIFGetByte ( $u );

			GIFDecoder::GIFPutByte ( $this->GIF_buffer );

		}

		$this->GIF_string .= chr ( 0x3B );

		/*

		   Add frames into $GIF_stream array...

		*/

		$this->GIF_arrays [ ] = $this->GIF_string;

	}

	/*

	:::::::::::::::::::::::::::::::::::::::::::::::::::

	::

	::	GIFGetByte ( $len )

	::

	*/



	/*

	 *

	 *  05.06.2007.

	 *  Made a little modification

	 *

	 *

	 -	function GIFGetByte ( $len ) {

	 -		$this->GIF_buffer = Array ( );

	 -

	 -		for ( $i = 0; $i < $len; $i++ ) {

	 +			if ( $this->GIF_bfseek > strlen ( $this->GIF_stream ) ) {

	 +				return 0;

	 +			}

	 -			$this->GIF_buffer [ ] = ord ( $this->GIF_stream { $this->GIF_bfseek++ } );

	 -		}

	 +		return 1;

	 -	}

	 */

	function GIFGetByte ( $len ) {

		$this->GIF_buffer = Array ( );



		for ( $i = 0; $i < $len; $i++ ) {

			if ( $this->GIF_bfseek > strlen ( $this->GIF_stream ) ) {

				return 0;

			}

			$this->GIF_buffer [ ] = ord ( $this->GIF_stream { $this->GIF_bfseek++ } );

		}

		return 1;

	}

	/*

	:::::::::::::::::::::::::::::::::::::::::::::::::::

	::

	::	GIFPutByte ( $bytes )

	::

	*/

	function GIFPutByte ( $bytes ) {

		for ( $i = 0; $i < count ( $bytes ); $i++ ) {

			$this->GIF_string .= chr ( $bytes [ $i ] );

		}

	}

	/*

	:::::::::::::::::::::::::::::::::::::::::::::::::::

	::

	::	PUBLIC FUNCTIONS

	::

	::

	::	GIFGetFrames ( )

	::

	*/

	function GIFGetFrames ( ) {

		return ( $this->GIF_arrays );

	}

	/*

	:::::::::::::::::::::::::::::::::::::::::::::::::::

	::

	::	GIFGetDelays ( )

	::

	*/

	function GIFGetDelays ( ) {

		return ( $this->GIF_delays );

	}

}

